Drug abuse is a well-known issue for a substantial minority of teenagers living in the U.S. and in many other countries. Possible consequences of this abuse include disrupted growth and development, conduct problems at home or in the classroom, increased involvement in risky behavior and increased chances of underperforming in school or dropping out of school. In a study published in 2014 in the journal Drug and Alcohol Dependence, researchers from several Canadian institutions examined the connection between preteen drug abuse, teen drug abuse and school-related difficulties. These researchers found that drug use in middle school increases the risks for certain negative outcomes in school. According to figures compiled through a National Institute on Drug Abuse-funded project called Monitoring the Future, relatively popular drugs of abuse among American teenagers include marijuana, synthetic marijuana, the ADHD medication Adderall, the opioid narcotic medication oxycodone (OxyContin), the opioid narcotic medication hydrocodone (Vicodin), the ADHD medication Ritalin, various hallucinogens, various inhalants and cocaine. Marijuana use is far more common among both younger and older teenagers than any other drug. Potential Reasons, Warning Signs A number of factors may help explain why any given preteen or teen gets involved in drug use, the American Academy of Child and Adolescent Psychiatry reports. Prominent examples of the most common baseline factors include the natural desire to experiment, the natural desire to explore boundaries and test rules, and the incomplete development of the mental faculties required to restrain impulsive urges or make sound decisions. Some children have increased chances of developing serious problems with drug abuse or drug addiction. Examples of the contributing factors here include feeling like a social misfit, having symptoms of depression, having low feelings of self-worth and having close family members with serious substance-related issues. Conduct problems and other school-related issues such as poor grades, poor attendance records and willful acts of truancy are commonly regarded as warning signs of teen drug abuse. Other possible signs include exhibiting unexplained changes in mood or personality, participating in disruptive conduct at home, associating with peers who are known or suspected drug or alcohol users, displaying a decline in physical energy and getting arrested or otherwise encountering problems with the criminal justice system. The Consequences In the study published in Drug and Alcohol Dependence, the Canadian researchers used a long-term project involving 4,885 teenagers to examine the consequences of adolescent drug abuse. These teens were first enrolled in the study during 7th grade. The researchers used information on drug use gathered while the participants were in this grade to help determine the negative outcomes of drug intake that manifested while the participants were in grades 10 and 11. Most of the potential outcomes were school-related, including disruptive conduct, poor academic performance and dropping out of school. Another potential outcome not specifically related to the school environment was the development of symptoms of depression. The researchers concluded that drug intake in the 7th grade acts as a predictor for significant conduct problems in 10th and 11th grade, as well as for increased chances of dropping out of school in either of those two grades. However, they also concluded that drug intake in the 7th grade does not act as a predictor for poor academic performance in the 10th or 11th grade, or for increased chances of developing symptoms of depression. The researchers found that some of the risks for dropping out of school occur as a result of having friends who use drugs or otherwise deviate from accepted social norms; however, drug use itself accounts for most of the risk. The researchers also found that some of the risks that teen drug users run for developing conduct problems stem from having friends who deviate from social norms, as well as from having relatively little interest in school or school-based activities. Considerations The authors of the study believe that the contribution of peer influences plays a significant role in creating school-related problems for teens who use\/abuse drugs. They also believe that drug use\/abuse and conduct problems, in particular, are mutually reinforcing phenomena.